Air heater for furnaces



Aug. 20, 1940. s. ALFlSl AIR HEATER FOR FURNACES.

Filed Nov. 29

INVENTQR am J O H m w Wm M wrrucgszs Patented Aug. 20, 1940 UNITED STATES "PATENT OFFICE, l 2,212,3"11" v AIR. EATER FOR FURNACES v I I Giuseppe Alfisi, Brooklym'N- Application November 29, 1) 38. Serial No. 242,881 0mm; (01.110415) This invention relates to air heaters for furnaces, and has for an object to provide'an' improved construction which issimple and yet effective in its Operation to cause the combustion of gases as well as cause an appreciable saving in coal while producing the same amount of heat.

Another object of the invention is to provide a heater air-supply device adapted to be connected to the door of anordinary heating furnace so as to swing inwardly and outwardly therewith.

A further object of the invention is to provide an air heater for supplying heated air to the gasesand flame immediately above the coal, the construction being such that the air is gradually heated until it is discharged at the inner and hottest end of the device. i

A further object of the invention, more specifically, is to provide an air heater formed in sections and with an air'shutter or control device exterior of the furnace, the "parts being so arranged that the sections will be interior of the furnace when the furnace door is shut.

In the accompanying drawing- Fig. 1 is a fragmentary perspective view of a conventional furnace with an embodiment of the invention applied thereto;

Fig. 2 is a longitudinal vertical sectional view through the air heating device shown in Fig. 1, the same being on an enlarged scale;

' Fig. 3 is a fragmentary side view showing several of the sections illustrated in Fig. 2;

Fig. 4 is a front view of the device as it is viewed from the outside of the furnace door;

Fig. 5 is a sectional view through Fig. 2 on the line 5 5;

Fig. 6 is a sectional view through Fig. 2 on the line 6-6; Fig. '7 is a sectional view through Fig. 2 on the line 'l--'l;

Fig. 8 is a sectional view-through Fig. 2 on the line 88;

Fig. 9 is a sectional view through Fig. 2 on the line 9-9;

Fig. 10 is a sectional view through Fig. 2 on the line |0'-IU, looking toward the furnace door.

Referring to the accompanying drawing by numerals, I indicates an ordinary conventional furnace with the usual door opening, 2, through which coal is adapted to be supplied to the furnace. The door 3 is hinged at 4, and is provided with a catch 5 adapted to be fitted into a notched latch member 5. The construction just described is old and well known.

To the door 3 is connected an air heating device the flame or gases rising'from the burning coal.

By providing heated air of substantially the 1 same temperature as the gases, there will be a readymixture of the air and gases which will readily" ignite "and, consequently, the gases will beconsumed and produce heat rather than the usual losses that are now experienced. In addition, by 'burning the "gases" the usual gas odors areeliminated; It will be seen, therefore, that byfproviding the'heated air as just set forth, objectionableodors are eliminated and a saving of coal is secured by reason of the extra heat provided by the combustion of the gases which usually pass out the chimney.

The heater 1 is provided with a number of sections, there being six sections shown in the accompanying drawing, namely, sections 9, I, ll,

[2, l3 and M. A spider or fitting I5 is carried by section 9, as shown in Fig. 2, and a pipe I6 is screwed thereon. The pipe l6 extends through an aperture or hole in the door 3 and has a hollow knob l'l' thereon exterior of the door. This knob acts in several capacities, including a nut for drawing the parts tightly together, as shown in Fig. 2. One or more washers may be used to space the heater inwardly from the door a'short distance. threaded extension I9 into which is screwed one end of a rod 20. This rod extends through suitable centrally positioned apertures in the various sections ill to M inclusive, and the sections are clamped together by a nut 20. It will be observed that each section, except section I4, is provided with an annular notch 2| so that the end or foot portion 22 of the next section may fit therein. Each section, except 9, is provided with a notch 23 for receiving the lugs or extension 24 of the next adjacent section. By thisarrangement, as'

The spider I5 is also provided with a parts tightly together while permitting the same to be separated for repair or other reasons.

Preferably the various sections are formed from cast iron, though they could be made from other material without departing from the spirit of the invention. The knob H, as illustrated particular ly in Fig. 2, is provided with an inlet aperture 25 which when the device is in use registers entirely or partly with an aperture 25 in a rotating plate 27, which plate acts as a shutter or damper for regulating the amount of air allowed to enter the heater.

In operation the heater is mounted on a door, as shown in Fig. 1, and when the fire is first started preferably the damper 21 is moved so that the aperture 26 will be out of registry with the aperture 25. However, after the fire has gained some considerable headway and begins to function to produce heat,.the shutter is gradually opened and may be set at any desired opening whereupon air will enter the heater and be discharged out through the aperture 8 at a temper;- ature substantially the same as the hot gases and flame in the furnace.

It will be observed that the section I0 is 'pr o-v vided with a number of apertures 28, while the section I! .is provided with apertures .29. .Sections l 2 andv l 3 are provided with apertures-3|] and 3!, respectively. These apertures are offset from each other so as to provide a more or lesstortuous passageway for the air and thereby delay its passage sufiiciently to permit it to be heated to the extent above mentioned.

By providing heated, air above the: fire, the

unburned gases which usually pass up the chimney are ignited so that a more eflicient heating action is secured and, consequently, an appreciable saving of coal. It will be seen, therefore, that the heater performs two principal functions, namely, the function of causing the gas to be consumed rather than pass up the chimney or into the room and, at the same time, results in the production of extra heat bythe combustion ofthese gases.

It will readily be observed that whenever the apertures 25 and 26 are out of alignment the heater will not function and, consequently, the furnace will function in the usual way of furnaces of the particular type used; However, as soon as the plate or disk 21 is rotated somewhat, so as to cause a registry or partial registry of apertures 25 and 26, the heater will begin to function to supply heated air to mix with the flame and the hot gases in the furnaceto secure a better combustion of the coal;

I claim:

An air heater for a furnace having a door, comprising a tubular member positioned to extend through said door, an air control valve connected to said tubular member exteriorly of the door, an end heating section positioned interiorly of the door formedwith a central bore having an enlarged portion whereby an annular shoulder is presented, a spider partly positioned in the bore in saidisection, saidspider. having an interiorly threaded tubular sleeve fitting in said central bore, a flange fitting-against said shoulderand; a threaded extension, said tubular memberbeing' screwed into said interiorly threaded tubular sleevefor. clamping said section against the interior of said door, a series of separable partly overlapping cup-shaped heating sections, one of said seriesof heating sections partly overlapping said end heating section, each of said series of heatingsections being fully open-at one end and at the other end being provided with-apertures,"

GIUSEPPE ALFISI, 

